a. Field of the Invention
The invention pertains to a process for preparing isobutyryl fluoride from carbon monoxide, propylene and hydrogen fluoride.
b. Description of the Prior Art
U.S. Pat. No. 2,831,877 describes a batch process for making carboxylic acids from olefins, carbon monoxide, an acidic medium such as hydrogen fluoride and water. However, the process is uneconomical because high polymeric acids and other compounds form, causing poor yields of carboxylic acids. U.S. Pat. No. 3,059,007 describes an improved process in which the mono-olefinic charge is hydrogenated prior to reaction to remove any polyolefinic materials which cause polymerization, but the resulting yields of mono-carboxylic acids are only 53.6 to 62 percent. European Patent Application No. 0-017-441 describes reacting a boron trifluoride catalyst and an alcohol in equal molar quantities, followed by separating the ester formed and the catalyst. This process cannot be used to form the isobutyryl fluoride. European Pat. No. 0,031,886 describes a process for making isobutyric acid or its lower alkyl esters, but such a process cannot be used to make isobutyryl fluoride. Belgium Patent No. 893,419 describes a slow semi-batch process for producing isobutyryl fluoride which decreases polymerization; however, the process is not suitable for a fast, commercially continuous process. Belgium Pat. No. 893,415 describes a fast, continuous, high pressure liquid process to form isobutyryl fluoride, but the high pressure equipment for the rapid flow rates is expensive. However, none of the above-mentioned prior art teach or suggest how to reduce the expensive costs of recovering and recycling carbon monoxide.
The present invention overcomes the expensive recovery and recycling of carbon monoxide of the prior art for a complex co-current gas-liquid reaction.